ALBUQUERQUE, N.M. -- The New Mexico teenager accused of gunning down five family members last weekend ambushed his father as he returned home from an overnight shift at a rescue mission, then reloaded his rifles and planned to go to a Walmart and randomly shoot people, authorities said Tuesday.
Instead, 15-year-old Nehemiah Griego texted a picture of his dead mother to his 12-year-old girlfriend, then spent much of Saturday with the girl and her family, authorities said. That evening, the teen went to the church where his father had been a pastor, and Griego eventually confessed to killing his parents and three younger siblings.
"The motive, as articulated by the suspect, was purely that he was frustrated with his mother," Bernalillo County Sheriff Dan Houston said.
Houston said Griego had planned the shootings for at least a week, but it's unclear if he ever actually went to a Walmart or why he changed his mind about continuing the attack.
Griego told detectives he also contemplated killing his girlfriend's parents, Houston said.
The sheriff's office identified the victims as Greg Griego, 51, his wife, Sarah Griego, 40, and three of their children: a 9-year-old boy, Zephania Griego, and daughters Jael Griego, 5, and Angelina Griego, 2.